17O NMR determination of proton sites in solid heteropoly acid H3PW12O40.31P,29Si and17O NMR, FT-IR and XRD study of H3PW12O40 and H4SiW12O40 supported on carbon
17O NMR determination of proton sites in solid heteropoly acid H3PW12O40.31P,29Si and17O NMR, FT-IR and XRD study of H3PW12O40 and H4SiW12O40 supported on carbon
复制标题
17O NMR 测定固体杂多酸 H3PW12O40 中的质子位点。碳负载的 H3PW12O40 和 H4SiW12O40 的 31P、29Si 和 17O NMR、FT-IR 和 XRD 研究
DOI：
10.1007/bf00806992
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发表时间：
1994
影响因子：
2.8
通讯作者：
H. Bekkum
中科院分区：
文献类型：
--
作者：
I. Kozhevnikov;A. Sinnema;R. Jansen;H. Bekkum
本文报道了固体杂多酸H_3PW_（12）O_（40）的~（17）O MAS NMR谱。固体和溶液17 O共振的比较表明，在固体脱水H3 PW 12 O 40中，W=O末端氧原子是主要的质子化位点。用NMR、FT-IR、XRD等方法研究了化学活性炭负载H3 PW_（12）O_（40）和H4 SiW_（12）O_（40）。碳负载的HPA保持其Keggin结构并形成精细分散的HPA物质。甚至在HPA负载量高达45wt%.31P，29 Si和17 O MAS NMR光谱的本体和碳支撑的HPA的显示HPA Keggin单元与碳表面的相互作用，导致大的线加宽的NMR光谱没有HPA晶体相的开发。
17O MAS NMR spectra for solid heteropoly acid (HPA) H3PW12O40are reported. Comparison of solid-state and solution17O resonances shows that in the solid dehydrated H3PW12O40terminal W=O oxygen atoms are the predominant protonation sites. H3PW12O40and H4SiW12O40supported on chemically activated carbon have been studied by means of NMR, FT-IR and XRD. The carbon-supported HPA's retain their Keggin structure and form finely dispersed HPA species. No HPA crystal phase is developed even at an HPA loading as high as 45 wt%.31P,29Si and17O MAS NMR spectra for bulk and carbon-supported HPA's indicate interaction of the HPA Keggin units with the carbon surface, causing large line broadening in the NMR spectra.